Recoil mechanism



2 Sheets-Sheet l Vista? RLLII: t.

V. F. LUCHT RECOIL MECHANISM Filed June 18, 1942 Sept. 19, 1944.

v. F. LUCHT 2,358,340

RECOIL MECHANISM Filed June 18. 1942 2 Sheets-Sheet 2 4 47 e46 44 70 Eg/ i( 1'/ 1'/ /L 779 G#- A 462 445 4a. 5 c' as Y f i# v A y l fs sa l lA *s Si 43 l Fi '7 Fi g l Syvum/vio@ Victnr Fl Lucht ably/MW PatentedSept. 19, 1944 UNITED STATES APATENT OFFRE 2,358,340 nEoorLMEoHANIsii/rA -Victor F. Lucht, Washington, D. C. Application June 1s,i942, seria1No.447,52u

(o1. ca -43) (Granted under the act of March 3, 1883, as

3 Claims.

amendedApril 30,1928; 370 O. G. 757) The invention described herein maybe manufactured and used by or for the Government for governmentalpurposes, without the payment to me of any royalty thereon.

An object of this invention is to provide a novel arrangement ofapparatus for controlling the movement of gun parts in recoil and/ orcounterrecoil.

Another object of this invention is to provide an improved structure formounting a recoil spring coaxially with a gun barrel.

Another object of this invention is to provide a gun recoil cylindercoaxially mounted around a gun barrel.

Another object of this invention is to provide a light and compactrecoil mechanism especially designed for mounting in an airplane whereinspace and weight requirements are exacting.

Another object of thisinvention is to provide a gun barrel having arecoil cylinder coaxially mounted thereon with fluid tight packingadapted to withstand the rather high temperature in the vicinity of thegun barrel.

Another object of this invention is to provide a recoil mechanism for agun having relatively short fluid flow passages.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

Figure 1 is a central cross sectional view and shows the position of theparts of the recoil and buffer mechanisms in their normal positionwiththe barrel B at one end of its operating stroke.

Figure 2 is a central cross `sectional view and shows the position ofthe parts of the recoil and buffer mechanisms when the barrel B is atthe other end of its operating stroke.

Figure 3 is a central cross sectional View and shows the position of theparts of the recoil and buffer mechanisms in one position of the barrelB as it returns from the position shown in Figure 2 to the positionshown in Figure 1 and said one position lies in a region defined bylimits MN wherein buffer action effecting movement of barrel B ispredominant.

Figure 4 is a sectional View taken substantially on line lI-4 of Fig. 3.

Figure 5 is a sectional View taken substantially on line 6-6 of Fig. 3.

Figure 6 is a sectional View on line 6-6 of Fig. 3.

Figure 7 is an enlarged view of the elements shown in the upper righthand corner of Fig. 1.

taken substantially Essential elements of my invention comprise supportvcylinder Ajbarrel B, piston cylinder C, sleeve D, cradle tube E andrecoil spring F. A pressure responsive valve having general referencenumeral G is carried by the piston cylinder C.

The barrel B is adapted to slide relative to aluminum support cylinder Acarrying spaced annular aluminum bronze bearing members IIJ, II, I2, I3,I4, I5, IB for providing a good wear? lng surface between barrel B andsupport cylinder A. The aluminum bronze bearing members I0, II, I2, I3,I4, I5, I6 are conveniently fastened to the support cylinder .A by meansof tongue and groove connections but it is apparent that the bearingmembers may be fastened to the support cylinder A by other means, forinstance, by a screw-threaded connection.

It is noted that the Support cylinder A has, at its downward end inFigure l, an annular L- cross sectional shaped flange I1 having internalscrew threads I'Ia thereon and has, at its upper end in Figure l, ascrew-threaded portion Iia for attachment of recoil mechanism inclosingstructure as will be seen later. A second support cylinder annularflange I8 having four` equally spaced fastening holes Ia therethrough isformed integral with flange I'I; and, the cylindrical structure producedby flange I8 isadapted to receive a fastening implement (not shown) bywhich the cradle tube or support cylinder A is fastened to supportcylinder E. Holes I8@ lare adapted to receive projections on saidimplement. v y

Cylinder piston C of steel is yfastened to barrel B by means of thecooperating nut kIll and connecter 20 which are each screw-threaded tothe cylinder piston C and barrel B respectively and hence cylinderpiston C has the same motion as barrel B. Cylinder piston C snuglysurrounds support cylinder A and slides thereon as the barrel B movesdue to recoil and/or counterfecoil forces.

The stationary cradle cylinder E having sleeve D snugly and fixedlymounted therein and having screw threads `Zlict'engaging supportcylinder screw threads I'Ia is closed at its upper end yin Figure 1 bymeans of screw-threaded follower 2I which engages cradle cylinderthreaded portion 20D. Screw threaded annular follower 2I (Fig. 7) isadapted to adjustably tension annular packing 22, 23 between bottomannular adapter 24 and annular movable vgland 25; top adapter 2Bseparates packing 22 from packing 23 and also annular dished membersV22a are disclosed in Figure 7 but it is apparent that other meanssimilar to dished members 22a are readily suggested by one skilled inthe art for providing aV fluid tight connection `between tube E andmovable cylinder pistonC.

Also, cradle tube E is formed with anvinternal annular shoulder c (Fig.7) which `is recessed so as to hold annular bushing 21, preferablyofhardened phosphor bronze so as to provide a suitable wear resistantstationary spring seat for recoil spring F. 'I'he other end of spring Fis normally biased against annular shoulder 28a (Fig. 1) on pistoncylinder C'so as to normally| press the piston cylinder C and attachedgun stationary cradle .head openings 10a.

alternately-placed about the annular valve casing V44. The valve casing44 besides forming a valveY seat for valve body 46 also cooperates withcylinder piston projection or piston head 10'for blocking fluid flowthrough openings 10a in the cylinder piston head 10 when the barrel Band associated cylinder piston C returns in counterrecoil; in recoil,valve casing 44, due to fluid pressure, is moved against bracket 43 thusallowing recoil fluid to flow through the cylinder piston Incounte'rrecoil the valve casing 44 moves against cylinder piston head 10and blocks fluid iiow through cylinder piston projection openings' 10aand substantially all the fluid flow in the vicinity of head 10 occursthrough l valve body opening 46a; however, fluid pressure actingronvalve body Wall 46d causes movement of valve body 46 against the actionof spring 48 barrel B downward to the position shown in Fig; l. Y y Fromthe structure thus far described it should be obvious that the gunbarrel B and associated cylinder piston C both recoil due to firing ofthe associated gun, and thereafter the .gun `barrel'l?. Vand. associatedcylinder piston C-return .tonor mal position under the influencev oftensioned refV coil spring F. f .3. l y.

The annular space between cylinder piston C and support cylinderrAV attheir upper ends in- Figs. 1 and 7 is made tight by the followingexpedient: annular packings 29, 3U separated vby gland 3| and adapted toconform to the abutting Y surfaces of annular support cylinder shoulder32 andannular gland 33 respectively is compressed by screwingscrew-threaded follower 34 on cooperating support` cylinder screwthreaded rportion 35. Y

Sleeve D (Fig. 2)v havinga cut-out fluid orifice or slotted passage 36of predetermined dimen- Vsions as will be described laterris maintainedin Vfixed relationshiptov cradle tube E by means of filling screw plugs31 which extend into sleeve circular hole 38 and is held by cradle tubetapped portion 39. Y

In the recoil oil filling operation screw-threaded plugs |31, 40 areremoved and` recoil oil is circulated into cradle tube opening 4| andout of cradle tube opening42 (Fig. 1) until the circulated oil flowsuniformly without discontinuity due to entrapped air in the compositerecoil cylinder. The recoil cylinder. for conning the recoil cylinderoil or similar fluid is defined bysupport cylinder A, cradle tube E andthe fluid tight connection comprising packing 22,23.V

The cylinder piston C carries the pressure responsive valve assembly .Gon the left hand end The valve assembly G corn-` thereof in Fig. 5.prises the following essential elements: annular bracket 43 threaded onthe end of cylinder piston C, annular valve casing 44 slidably mountedon cylinderpiston C,V Valve guides 45 screw-threadedly mounted on valvecasing 44 and 'cooperating v withV the bracket guide holes 43a, valvebody 46 45an d valve bodies 4B Vare that the guide pins 41 for holdingvalve in the valve casing hollow portion 44aV valve casing open-i l andtends to close port 44b thus causing the barrel B` to return incounterrecoil with limited velocity inthe region defined by the limitsVM,-N -(Fig.1). Y t

It is noted that the cylinder piston C carries two spacedannularprojections or heads 10, 1| each havingouter bearing surfaces adapted tomake close sliding contact with the sleeve D which-has two diametricallyopposite throttle openings 3B therethrough (Fig, 4). l,Sleeve -open,

ings 36 are designed to offer resistancetoiiuid flow in adegreevdepending upon the position of cylinder piston C whereby thecylinder piston C and Vbarrel, B travel with substantially variablevelocityV notwithstandingfthat substantially constant propelling forcesare exerted on theY barrel B. It is also noted that due-to the spacingof cylinder annular heads 10, 1| with respect to sleeve Dcorrespondingly different size orifices'are formed at the sleeve wherethose annular projections contact thesleeve.

In order to understand the controllingrforces exerted on cylinder pistonC in its movement one important fact must be understood, namely, that onrecoil the sleeveaperture formed Vby the cooperation ofrcylinder pistonhead 1| will be controllingV since the brakingV effect of ythe other,

annular projection is made ineffective due to the large holes 10auncovered when thevalve casing 44 is moved to the left in Fig. 5; andthat on counter recoil in the range defined by M, lN shown on Fig. 1 theaperture formed by annular piston 'head 10 with sleeve D is Vof smallrelative size kther limit the fluid flow through portY 44h and furtherretard the movementof the cylinder-piston C in counterrecoil.V

In Vcarrying out one rrecoil and counterrecoil Y stroke it is noted thatboth valve casing 44 and valve body'46 each individually serve asa'valve body for the control'of fluid flow.`

Resilient disc of leather or. similar material fastened to nutV I9 as bymeans of screws 80a serves to absorb some of the shock;between thecradle tube and barrel when it returns to normal position'(Fig. 1)k atthe end of the counterrecoil= stroke. Y

. Operation-In the recoilk o f the gun, the parts being in the positionshown in Figure l, the braking fluid to the right of the valved piston10 will pass freely through said piston and through the ports.46ajinthevalve 46, and 44a in valve casing 44, which ports are now ginning ofthis stroke pressure. of the Voilagainst the right end 0f ther/alf@casing. causes the4 in registry. `At thebesame to move slightly to theleft against the pressure of spring 48, and away from the piston 'IUthus providing a space between said piston and casing to permit fluid topass freely through the opening 16a of the piston 10. During thismovement of the valve casing 44, the ports 46a and 44h remain inregistry. Upon counterrecoil the reaction of the spring 48 forces thevalve casing 44 against the piston 1|) closing the opening 18a. Thepressure to the left of the valve 46 will cause it to move back into itscasing 44 against the pressure of spring 48 and close the ports 46a and44h and prevent the passage of oil therethrough. When the gun reachesbattery position the spring 48 will return valve 46 to normal positionwith ports 46a and 44h again in registry preparatory to the repetitionof the cycle. In normal or battery position, as shown in Figure 1, thevalved recoil piston 1I occupies the position N. In this position theleft end of the passage 36, from N to M does not function during recoilstroke, but only that portion of the passage from N to the tapered rightend. Valved piston Ill resists somewhat the counterrecoil movement ofthe gun by reason of the closing of the valve 46 but this does notinterfere with the operation of the piston 'H during counterrecoil untilpiston reaches position N in Figure 3, that is to say, at the point ofthe passage 36 Where it leftl end begins to taper off. During the lastpart of the counterrecoil or from about point N to M, piston 10, (theValves of which are closed during counterrecoil), meets with increasingresistance due to the decreasing taper of the left end of the slottedpassage 36. The valved piston 'I0 thus provides a buffer action at theend of the counterrecoil stroke of the gun.

I claim:

1. In a recoil and counter-recoil apparatus for a gun barrel, thecombination of a gun barrel, a stationary tubular supporting memberprovided with internal bearing surfaces for the said gun barrel, atubular member mounted for sliding movement on the external surface ofthe said tubular supporting member, the said tubular sliding member andthe said gun barrel being secured together at one end thereof to move inunison, a second stationary tubular member surrounding the said tubularsliding member and spaced therefrom to provide an annular fluid space, arecoil spring within the said annular space, and a piston on the saidtubular sliding member in sliding engagement with the internal surfaceof the second said tubular member.

Cil

2. In a recoil and counter-recoil apparatus for a gun barrel, thecombination of a gun barrel, a stationary tubular supporting memberprovided with internal bearing surfaces for the said gun barrel, atubular member mounted for sliding movement on the external surface ofthe said tubular supporting member, the said tubular sliding member andthe said gun barrel being secured together at one end thereof to move inunison, a second stationary tubular member surrounding the said tubularsliding member and spaced therefrom to provide an annular fluid space, arecoil spring within the said annular space, and a pair of pistons onthe said tubular sliding member in sliding engagement with the internalsurface of the second said tubular member, one of the said pair ofpistons being provided with valves.

3. In a recoil and counter-recoil apparatus for a gun barrel, thecombination of a gun barrel, stationary tubular Supporting memberprovided with internal bearing surfaces for the said gun barrel, atubular member mounted for sliding movement on the external surface ofthe said tubular supporting member, the said tubular sliding member andthe said gun barrel being secured together at one end thereof to move inunison, a second stationary tubular member surrounding the said tubularsliding member and spaced therefrom to provide an annular nuid space, arecoil spring within the said annular space, the second said tubularmember being provided in its internal surface with a slotted passagehaving a maximum central opening and tapering toward the breech end ofthe barrel and toward the muzzle end thereof, and a pair of pistons onthe said tubular sliding member in sliding engagement with the internalsurface `of the second said tubular member, one of the said pistonsbeing, in the battery position of the said connected barrel and tubularsliding member, substantially at the juncture between the said maximumcentral portion and the said tapered breech end portion of the slottedpassage, and the other of the said pistons being substantially at theend point of the said tapered end portion, the last said piston beingprovided with Valves adapted to be closed during the counter-recoilstroke whereby the said valved piston cooperates with the said taperedbreech end portion of the slotted passage to buffer the last portion ofthe said counter-recoil stroke.

VICTOR F. LUCHT.

